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2.04.7 Hydrology Description <br />2.04.7(1) Groundwater Information <br />Drilling information obtained to date does not indicate the occurrence of a widespread <br />water table associated with an unconfined aquifer. Three stratigraphic intervals have <br />been determined to hold and transport varying quantities of groundwater. One is a 1.3 <br />foot thick zone at the base of the Lewis coal zone in the north end of the proposed pit. <br />This zone is monitored by Well 17B where it is located 45.6 to 46.9 feet from the surface <br />(Map 4-3). The second water bearing zone consists of a 96 foot thick interval extending <br />from the top of the Shamrock coal zone to the base of the Carbonera coal zone. This <br />zone was monitored by Well 82-5 where it is located from 101.3 to 197.5 feet from the <br />surface (Map 4-3). The third water bearing zone consists of a 17 foot thick zone adjacent <br />and above the Shamrock Rider Coal Zone. This water zone will be monitored by Well <br />82-4 although its occurrence is outside the planned pit disturbance. The zone was <br />intercepted 383 to 400 feet below the surface in Hole 82-4 (Map 4-2, Surface Geology <br />Map). <br />The strata bearing these water zones dip 27 to 30 degrees to the southeast, extending <br />beyond the permit area and beyond the adjacent area. Lithologically these water bearing <br />zones occur in fractured strata and donot appear to be interconnected or contiguous. <br />Fractured shales appear to be the dominant source of water although limited water can <br />also occur in the coal seams. Vertical communication may also exist between certain <br />areas by faulting although no faults have been found in the current mining area. <br />Correlation of drill holes resulted in the identification of potential faulting or other <br />thickening and thinning of strata. <br />No seasonal variation of these waters hasbeen observed. The monitor wells are not <br />pumped; consequently no changes in water quality havebeen observed. Well 82-5 was <br />destroyed as the mining progressed to the north and wasno longer available for any use <br />in monitoring. <br />There are no known uses of the water in these three water bearing zones. Based on <br />current drilling information, there is no free water table. The permittee is the owner of <br />any and all groundwater resources by virtue of its surface ownership. <br />Groundwater quality analyses for the water samples taken from drill holes 17B and 82-5 <br />are contained in Table 4-2as well as in the separate Annual Hydrologic Reports <br />submitted to the Division from 1995-2006. <br />Recovery analyses were attempted on the water bearing zones at Wells 17B and 82-5. <br />The data for Well 17B is illustrated on Table 4-3 and Figure 4-2. The results yielded a <br />transmissivity value for the monitored zone of 0.01 gpd/ft. The zone is considered too <br />small for consideration of recharge and storage characteristics and for beneficial use. <br />Abridged Permit Document4-11Permit Renewal RN04 4/2014 <br />